• WCB Carbon Steel Material:The valve body is cast from ASTM A216 WCB carbon steel, featuring excellent mechanical properties, high yield strength, strong pressure-bearing capacity and cost-effectiveness. It is suitable for medium and high-pressure applications with non-corrosive media.

• Reduced Bore Design (6x4" Reduced Bore):6-inch valve body with 4-inch reduced bore flow passage. The valve body features a large pressure-bearing area and sufficient wall thickness to meet 300LB pressure class requirements. The reduced-bore ball is lightweight with low operating torque, reducing actuator size and cost, achieving a balance between economy and performance in large-bore applications.

• Trunnion Mounted Ball Design:The ball is supported and fixed by upper and lower trunnions. Initial sealing is achieved by seat spring preloading, with medium pressure assisting to enhance sealing performance. Operating torque is significantly lower than that of floating ball design, avoiding excessive ball displacement caused by pressure differential under medium and high-pressure large-bore conditions, ensuring stable and controllable opening and closing.

• Two-Piece Body Design:Compact structure for easy maintenance and replacement of internal parts, reducing system downtime.

• Flanged Connection:RF (Raised Face) or RTJ (Ring Type Joint) flanged connection is adopted in accordance with ASME B16.5 standard. The 300LB pressure class ensures reliable connection under medium and high-pressure conditions.

• Fire-Safe Design:Compliant with API 607 / API 6FA standards. Graphite packing and metal sealing structure maintain sealing integrity in case of fire to prevent media leakage.

• Anti-Static Device:Built-in anti-static spring or wire ensures electrical continuity between the ball, stem and valve body, reducing fire and explosion risks.

• Stem Blowout-Proof Design:The stem adopts a top-entry blowout-proof structure to ensure operational safety.

6x4"300LB WCB Reduced Bore Trunnion Mounted Ball Valve 3D Diagram

J-VALVESSPE can supply a range ofseat types and configurationsto meet specific process needs:

J-VALVES trunnion mounted ball valves standard seat ringsare soft-seated by the use of athermoplastic or elastomeric or Meta

Seats-Tungsten /Chrome carbide /ENP

Single Piston (SPE) , Double Piston effect (DPE) and Combination (SPE x DPE) seats are available.

Seat Princlple

Two independent seat rings grant the sealing, barrieragainst the line pressure actingon the upstream and downstreamsides of the valve which allows the valve tobe bidirectional.

A set ofcoil springs acting, between the upstream side ofeach seatring,andthe body,generate an uniform thrust on theseat which push the same against the ball and grant the sealingfeature with no orverylow pressureinthe line,when the line pressure increasethe thrust actingon theseat increases proportionally and the sealing leatureis granted throughout the fullpressure range.

The J-VALVES SPE trunnion mounted ball valves are available with Double

Block & Bleed in dependent oftheseat type.

Valve seating variations

Seat Design	Single piston effect (SPE)	Double piston effect(DPE)-DIB 1	Combined DIB 2
Bi-directional sealing	Yes	Yes	Yes
Body-Cavity Self relieving	Yes	No	Yes
Double Barrier	No	Yes	Yes (preferred direction only)

Single Piston Effect

Single piston effect (SPE) is the stand ard feature for theseat rings of the J-VALVES SPE trunnion mounted ball valves.

On a SPE seat ring:

The pressure ac tingon the upstream side ofthe seat ringgenerates aforce which push theseattowards the ball.The pressure actingon the downstream side ofthe seatring generates a force which pull theseatring away fromthe ball.

Anyoverpressure which may be generated by the thermal expansion of the fluid trapped in thebodycavity with the ballin fully closed position, will beautomatically dischargedinthe line on the lower pressure side.

Double Piston Effect

Double piston effect(DPE) is a stand ard feature fortheseat rings ofthe J-VALVES trunnion mounted ball valves & recommended forwelded body valves. Ona DPE seat ring, both the pressure acting on the upstream sideof theseatring andthe pressure acting on thedownstreamside of the  seatring, generatea forcewhich push the seattowards the ball.

With th is type ofseat ring,the eventual over press ure whichmay be generated by the thermal expansion ofthe fluidtrappedinthebodyeavitywith theball in fullyclosed position,can be discharged by the use of:

An external safetyrelief device.

The Double Piston Effect grants a double sealingfeature,iftheupstreamseat ringisdamaged, thedown stream seatgrant the sealingfeature of the valve.